fcntl and sceKernelFcntl read a third argument as a 64-bit integer for
every command on a non-socket descriptor. F_GETFD and F_GETFL pass no
third argument, and the commands that take one pass an int or a pointer.
They now read nothing, an int or a pointer, by command. An int read as
a 64-bit value kept whatever the caller left in the upper half of the
register, so F_READAHEAD -1 enabled read-ahead instead of disabling it.
ioctl and _ioctl answered EBADF for every descriptor outside the
libSceNet socket table. Decoded call sites: PS5MC (PPSA99420, FIONBIO x3,
FIONREAD x2, TIOCGWINSZ x3), ProsperoTV (PPSA99003, FIONBIO on a pipe
once poll on pipes is in), XPSemu (PPSA97358, 21 sites).
Following FreeBSD 11.4 kern_ioctl (sys/kern/sys_generic.c:758),
vn_ioctl (sys/kern/vfs_vnops.c:1488), pipe_ioctl (sys/kern/sys_pipe.c:1346)
and randomdev_ioctl (sys/dev/random/randomdev.c:301), release/11.4.0
8c639945: FIONBIO sets or clears O_NONBLOCK through the same status
flags as fcntl F_SETFL (EFAULT for a null argument before EBADF);
FIONREAD reports the size past the offset of a file, the queued bytes of
a pipe's read end, 0 on its write end, ENOTTY on the random device, and
throws on a directory or another character device; termios requests
(group 't', TIOCGWINSZ included) fail with ENOTTY, as tcgetattr already
takes these descriptors as not a terminal; any other request throws
naming the request and descriptor kind. Sockets keep their path
unchanged.
Co-Authored-By: Claude Fable 5.1 <[email protected]>
fcntl and sceKernelFcntl answered EBADF (sceKernelFcntl threw) for
every descriptor outside the libSceNet socket table, so files, pipes,
directories and descriptors 0 to 2 could not be queried or changed.
Observed: Yamagi Quake II (PPSA99007) stops with
"Sys_Error: change stdin to blocking Bad file descriptor", from
fcntl(fileno(stdin), F_SETFL, fcntl(0, F_GETFL, 0) & ~FNDELAY)
(yquake2 src/backends/unix/system.c:81-86).
Predicted from the titles' sources and decoded call sites: XPSemu
(PPSA97358, 97 fcntl sites: F_GETFD 12, F_SETFD 20, F_GETFL 8,
F_SETFL 9, F_DUPFD 1, F_DUPFD_CLOEXEC 7, F_GETLK 9) fails in
qemu_init_main_loop, where its pipe2 (pipe plus F_SETFD FD_CLOEXEC) and
glib's g_unix_set_fd_nonblocking (F_GETFL, F_SETFL) build the event
notifier (util/event_notifier-posix.c:44-67); VLC (PPSA85300, 43 sites,
F_RDAHEAD on every file it opens), RetroArch (PPSA99169, 17),
Porpoise (PPSA99764, 13) and Ruffle (9) call it on files and pipes.
The commands follow FreeBSD 11.4 kern_fcntl and kern_dup
(sys/kern/kern_descrip.c:479-799, 812, release/11.4.0 8c639945):
F_GETFD/F_SETFD keep the close-on-exec flag per descriptor, F_GETFL
reports the host access mode with the status flags, F_SETFL changes
only O_NONBLOCK, O_APPEND, O_ASYNC, O_FSYNC, O_DIRECT and FRDAHEAD,
F_DUPFD/F_DUPFD_CLOEXEC give the lowest free descriptor at or above the
start through dup (EINVAL for a negative start), F_DUP2FD goes through
dup2, F_RDAHEAD/F_READAHEAD set FRDAHEAD on files (EBADF on pipes,
ENOTTY elsewhere), and unknown commands fail with EINVAL. Status flags
live in a guest table shared by dup, dup2 and F_DUPFD like an open file
description. O_NONBLOCK switches a pipe (PIPE_NOWAIT on Windows, where an
empty read and a full write now report EAGAIN; the host flag on Linux).
Record locks use the host POSIX locks on Linux and throw on Windows.
Changes the host cannot model throw naming the flag and descriptor kind.
Sockets keep their path unchanged.
Co-Authored-By: Claude Fable 5.1 <[email protected]>
Direct memory can already be mapped more than once, so there is no
aliasing to enable and the call returns 0. ProsperoEden (PPSA99008)
imports it and calls it before mapping the same direct memory again.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
* fix(agc): keep the driver's per-thread scratch out of thread_local teardown
With MinGW's emulated TLS, a thread_local with a destructor in a DLL is
destroyed after its storage is gone: when a std::thread ends, winpthread
runs libgcc's emutls key destructor, which frees the thread's thread_local
storage, and only then does the loader's DLL_THREAD_DETACH run the DLL's
tls_atexit list, so the destructors run on freed memory. The queue worker
touches four of them in libSceAgcDriver (the dispatch-ahead map, the
pending waits, the draw-snapshot compare vectors and the image decode
memo), and Driver::stop's join of the worker then corrupts the heap.
Under cdb's checking heap agc_driver_draw_cache_reuse stopped at the
worker's exit with heap corruption in all 127 runs, with graphics
pipeline libraries, with APS5_NO_PIPELINE_LTO=1 and with APS5_NO_GPL=1.
Without it the damage shows intermittently, as exit 0xc0000374 (2 of 143
runs with a cold NVIDIA shader cache) or as a fault in whatever allocates
next, such as NVIDIA's compiler on the optimized-link thread (#2980).
These objects now live in HostThreadLocal, fiber-local storage that owns
them, as the recorder's buffers do since e424b6b7b.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
* fix(libs): keep thread_local objects with destructors out of module teardown
The teardown order behind the driver's heap corruption holds in every
module: with MinGW's emulated TLS a thread's thread_local storage is freed
before the module's DLL_THREAD_DETACH runs its thread_local destructors,
so they run on freed objects. PreciseSleepUs's timer (used, among others,
by the video-out vblank thread) then closes a stale handle; libkernel's
directory path, socket waker and UUID random device, libSceRandom's random
device and libScePosixForWebKit's random device and host lookup free or
close stale objects. They move to HostThreadLocal. The other thread_locals
in the modules are trivially destructible or only built for Linux.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
* test(libs): fail when a module registers a thread_local destructor
prx_thread_local_destructors lists the symbols of every built module and,
where MinGW's thread_local destructor support is linked in, disassembles
the module for calls to __cxa_thread_atexit outside libc's registration of
guest destructors. A module that keeps a thread_local with a destructor
fails it with the function that registers one: with main's libSceRandom
it reports sceRandomGetRandomNumber, and with this branch all 122 modules
pass, libc being the only one that links the support.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
* fix(agc): keep the image memo behind its pointer
The image decode memo went into HostThreadLocal as the whole array. On
Linux, where HostThreadLocal is a plain thread_local, that put 1024 memo
entries into every thread's TLS block instead of one pointer. It keeps
its unique_ptr as before, now owned by HostThreadLocal, so Linux builds
the same thread_local as main.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
---------
Co-authored-by: Claude Opus 5.5 <[email protected]>
Co-authored-by: Dean Galvin <[email protected]>
Dean